Custom editor window for editing prefabs

The changes I make through my custom window are not saved to the prefab. And if I make a change to the prefab through inspector window, the prefab in my editor window gets lost. If I drag the prefab into the scene and make changes through my editor window, it changes the object in the scene but not the original prefab. I am very confused with the new system. Why doesn't my editor window apply changes like it used to? How do I edit my prefabs in the new system through my custom editor window?

 

A simplified version of my code:
I drag the prefab from project window to the objectfield.

Code (CSharp):

1. public class WavemachineEditorWindow : EditorWindow
2. {
3.     private Wavemachine wavemachine;
4.  
5.     void OnGUI()
6.     {
7.         wavemachine = (Wavemachine)EditorGUILayout.ObjectField(wavemachine, typeof(Wavemachine), false, GUILayout.Width(200));
8.  
9.         wavemachine.someValue = EditorGUILayout.IntField("Value:", wavemachine.someValue);
10.  
11.         if (GUI.changed)
12.         {
13.             EditorUtility.SetDirty(wavemachine);
14.         }
15.     }
16. }

 

Okay I kinda figured out the PropertyField thing. This line seems to be working BUT it feels VERY IMPRACTICAL.

inside OnGUI():

Code (CSharp):

1.  
2. myWM = new UnityEditor.SerializedObject(wavemachine);
3. myWM.Update();
4. myWM.FindProperty("waves.Array.data[0].wavethreads.Array.data[0].subwaves.Array.data[0].amount").intValue = EditorGUILayout.IntField("amount:", myWM.FindProperty("waves.Array.data[0].wavethreads.Array.data[0].subwaves.Array.data[0].amount").intValue);
5. myWM.ApplyModifiedProperties();
6.  

Am I doing this the right way?

I have many variables that I edit with my custom editor window, do I have to type them all in this way? In the manual it says shift+right clicking gives the property's path. Is it possible get it via code so I can maybe write my own method that takes the variable as parameter, and generates the above code for it.

 

Hey, I'm not sure if this is still relevant for you, but it might be for someone else. Here is a link to how it's done properly:
https://stackoverflow.com/questions/61677236/unity-custom-editor-prefab-show-modified-values